(Phys.org) —A team of researchers working at Northwestern University has found that tin selenide (SnSe) has the highest Carnot efficiency for a thermoelectric cycle ever found, making it potentially a possible material for use in generating electricity from waste heat. In their paper published in the journal Nature, the team describes work they’ve conducted on SnSe and how their discovery might lead to even more efficient materials. Joseph Heremans gives a short history of thermoelectric research in a News & Views companion piece and offers some insights into why SnSe might be so efficient and how it might lead the way to the discovery of even better materials.